This is rather very easy and most of you must be aware of how to deactivate Buzz in Gmail, but I struggled to find the option when I wanted to turn it off for the first time. So for others like me, I’ll mention the steps to hide Google Buzz from your Gmail in this post.
To turn off Google Buzz in your account, you need to login to your Gmail account and scroll down to the bottom of the page and locate the links in the second last line which looks like this -

Yes, there you have the ‘turn off buzz’ link. Click on that and you’ll not see the Buzz menu again in your Gmail until you turn it on.
To activate buzz, your will have to go to the same place as mentioned above and now you will see “turn on buzz”, if you have turned it off earlier, click on that link and the Buzz is all up again.